Reciprocating carriage motion



Sept, s, 1959 S. R. STENSTROM RECIPROCATING CARRIAGE MOTION Filed Oct. 31, 1955 INVENTOR 2 Sheets-Sheet 1 M Q w Mw. Ww

Sept. 8, 1959 s. R. sTENsTRoM 2,902,866

RECIPROCATING CARRIAGE MOTION Filed oct. 31, 1955 2 sheets-sheet 2 1N VENTOR BY/QMWMIM A ORNEY I :entrasse nmcrPRocnrmo Morton y t LStenRiohardStenstx-om, .':Irollhattamswedcn y 'Application,ontnemenrasssenaiNn..s4s,sn1

- nicmar. rcx. 'I4-fer) .'llis, inventicnrelates ,to improvements .in the drive d .drive-.controlf the .typelheds .of printing presses Q'f theme-,revolution g .Angbljeetof .Linventionis .to secure ,absolute register 'between the type and .sheet being ,printed .by `exact controlhof thespeedofrnovement .of .the type-.bed whlle engaged ,with .the .impression `cylinder tof l,the -ypress- .According to-.this invention Ya printing press, for instance,.n.tvvofrevolutionpress, .having areciprocatingtypeb.ed.is provided which, fduring .the ,printing .and return periods. .is arranged .for .being :driven -by racks attached to.the.t,vpebed,.alterfnate1y engaging in ...driving .shuttle Whel, .'lldwhich during ltlrdation rand acceleration periods at the .end pnsitions .is arranged .to receive vits motion by means of turning forks l.triade vin one piece -attache'd to the movable type-bed, cooperating with swingaible'rrns fitted with rollers, these rollers entering lgrooves limited by the'legs 'orshanks of the forks. f In presses of Jr'the ^tworevolution ftype, -the impression cylinder rotates two turns during a complete printing operation, during which .time ,six ,diierent periods 4of motion can be discemedfor the reciprocating type-bed, as follows:

It. Printing period, v'during which the :type bed has vconj ='s tant"speed f Y II. rRetardation period f (with stop Jand -reverse) Htl. Acceleration'period ILV..` Retur'n -period v( atconstant'speed) V5 ZRetardation-period(Wirth-stopandreverse) VILAcceleratiomperiodwe e During the printing period, an absolutely constant type-bed synchronous with the peripheral velocity of the impression cylinder is required, in order to secure exact register. Previously, considerable diculties were encountered in attempting to attain uniform running, and consequently a perfect print. These diiculties have been entirely overcome by the present invention, while at the same time the dimensions of the press can be reduced considerably.

The invention is mainly characterized in that the fork grooves individually are straight in their interior part and become wider towards their outer part, owing to the fact that this partly groove-limiting part of each of the two fork legs is shaped as a curve, the curve center and curve radius of which differ from those of `the arc belonging to the other fork leg portion.

In the accompanying drawings an embodiment of the invention is represented by way of example.

In the drawings- Figure 1 is a side View of a press according to this invention;

Figure 2 is a transverse vertical sectional view on the line II--II of Fig. 1;

Figure 3 is a plan view of the elements associated with the inner frame, with the type-bed removed, and the outer frame omitted;

Mice

Figure .4 ris a diagrammatic .representation ,of .the .drive of a swingable arm .used lfoi-controlling theiypeebed `of lthe press .-in itsend `position; and

-F'gllre ,5 isaan :enlarged diagrammatic sectional View illustrating the shape of the turning fork of the drive.

In the -accorrtpaliytlfs' drawings reference numeral .1 designates lafsideof the-rnainstand or frame of .thepress while tthe other side rportionof the main `frame is .designatedbymumeral ,2. fNumerals 3 `and 4 indicate -the end portions respectivelygofthe mainframe. Withinthe mainframe ,lis located .an ginnerrframe, ,the two side jpor- .tions =of Wl1ic2l.1.;are indicated eby 5 and i6, respectively. The principal :mechanism y:for operating the reciprocatory type-,bed Vofthe tpressjs mounted in :or associated with the f inner :frame 5, :6. .Extending transversely lthrough one side portion 6 of the inner frame and v"through- Side portion rlzof .fthevmainfrarne-isa drive shaft Thaving one end aportion, foutside V.of :the main iframe `vvall it, a frnain driving 'wl1eel;.8, illustrated zas a rgear ibutwhich .obviously could abe a pulley.

ilhe rdriving :power for 1'operating the--type-bed, supplied to the press through zgearawheelzSE-andshaft 7 ,is/transmitted-:through gearwheel1ti,.mounted on shaft f7 to two `gear vif-heels f1=1,]i2, which :ai-erin mesh witheach other. :Gear wheels 11 .fand :12 are :mounted f on 'transversely extending Shafts i14- arrd L15 rrespectively, .carried by inner frame walls 5 and 6. Gear wheel 11 is in mesh-zwithra shuttle Wheel 16, :andggear rwheel l2 :Withgshuttle y.wheel :17. 'The Shuttle-wheels 16;and 11H .gare .mounted on shafts'd9rand 26., zrespectively, :and .are .fslidable Vs'idewlise ron said shaft. This sidewizse .motion fof .the :shuttle `wheels '.116 and '17 is .obtained 'fromrtwo 'twofarmed .levers A21 tand 22, 'which are pivotally mounted on brackets 25 and l26, `respectively, intermediate :of their ends. The :upper ends of the levers .are :provided :with laterally extending forks l2f3, 2:4, zrespectvely, '.which engage in slots 218, 118' of shuttle .wheels 116, 717, respectively, and serve (to slide the shuttle :Wheels :laterally :of .the -press upon action of rlevers 221 22, thy Imechansrnto be described.

alnftheilowergportiomof the main frame and of rthe inner frame vof :the rprs Sis mounted Aa transversely extend-ing shaft 127, having .a .driving :gear wheel 28 mounted there-` on. Gear wheel 28 meshes with `and is driven by -gear wheel 29 tfxedly mountedlonrtransversely extending shaft 14 on the other end of which is mounted gear wheel 11. Shaft 27 is thus provided with intermittent turning motion, and is provided with `a cam 31 which turns therewith. The end portions 34 and 35, respectively, of twoarmed levers 21 and 22 are arranged to engage with and be operated in an intermittent reciprocatory motion by roller 36 operatively connected with cam 31 by means of link 37 and linkage bolts 38, 38', respectively.

The arrangement or system is such that, when the press is running, the type-bed 39 is driven in one direction by the shuttle wheel 16, and in the other direction by the other shuttle wheel 17, since the shuttle wheels turn in opposite directions, while the cam 31 attached to shaft 27 regulates the time intervals, during which one shuttle wheel or the other one is in mesh with the respective racks 42 or 43 attached to the underside of the type-bed 39 from the supporting slideways. The impression cylinder of the press is indicated by reference numeral 48.

In the end portions of the type-bed turning forks 49, 50 are arranged, into which engage swing arms 51, 52, respectively, driven by means of levers 54, 55, respectively, from gear wheels 11, 12, respectively. The inner ends of lever 54, 55 are pivotally connected Wit-h crank pins 53, 53 respectively, on gear wheels 11, 12. The free ends of arms 51, 52 suitably are provided with rollers 56, 57, respectively. The opposite ends of swing arms 51, 52 are pivotally mounted on brackets 58, 59 respectively,

secured to the machine frame. is controlled in its turning movement (retardation, turning and acceleration periods. The beginning of mesh and release respectively after the acceleration period is elected while the type-bed has constant speed, in other words, during the printing and return periods.

The shape of the curve of the turning forks is so adapted that rollers 56, 57 of swing arms 51, 52, which performs an oscillatory movement along a circle shaped arc can be caught in the fork when it is moving at constant speed by moving upwards in same. The difference between the linear motion of the roller and the fork is compensated by the upward and backward movement ofthe roller in relation to the movement of the type-bed. The retardation force generated is taken up by the roller and is transmitted to driving gear wheel 8. This force brings about angular acceleration of the driving shaft, and, naturally, also of the other shafts in the system, but the degree of inequality can be made insignificant by a suitably dimensioned swing mass.

The retardation movement of the roller which is generated by a rotary motion will become harmonic or nearly harmonic, that is, the force varies in a linear manner with the travel. During the acceleration period, the energy stored in the ywheel (not shown) of the press is used for increasing the speed of the type-bed.

When studying the desirable curve shape of the turning fork it is found that there must be two different paths of motion for the roller center; one for entering and one for leaving. The motion is not quite symmetrical, as will be seen from Fig. 4.

When the roller enters the turning fork, the inner crank pin is at about 15 in front of point I, and the lever is in position A, Fig. 4. A small angular motion clockwise motion lof point x along arc AC as a motion of the same size placed symmetrically after point II, situated 180 after point I.

The inner shape of the turning fork is shown in outline in Fig. 5 where R=roller radius. The distance a between the curves for in-and-outgoing motion will be, for instance, in a press for 100 cm. width of paper about 0.3 mm. at the entrance to the fork (the shuttle wheel in mesh with the rack) and decrease to 0 in the position corresponding to the beginning of the turning period, when the shuttle wheel is released from the rack. The roller thus lies in the fork without play during the turning movement.

That part of the curve which is Working during the In this way, the type-bed 'i turning period properly speaking can -be straight with a larger or smaller inclination, when the turning movement will become harmonic with a turning path somewhat depending upon the inclination' and a final force depending upon same as a consequence.

I claim:

In a printing press having a reciprocating type-bed provided with a pair of driving racks adapted to be alternatively driven -by periodically meshing with driving shuttle wheels during the central parts of the movement of said type bed, and during the end portions of its, movements, during retardation and acceleration is driven through turning forks attached to the type bed, said forks having legs spaced apart providing grooves therebetween which are engaged by swing arms having rollers which enter into grooves formed by the legs of said forks, the improvement residing in that said forks each consist of a single piece and are of such shape as to provide grooves limited by walls which are comprised of straight, .parallel inner parts, and outer parts which curve outwardly, the centers of curvature of the curves of the said outer portions of the respective legs being on the same' side of said slot so that said outer portions of said legs curve in the same direction, the radius of curvature of the curve of the outer portion of the leg on the side of said slot located 'closest to said centers of curvature being smaller than the radius of curvature of the curve of the outer portion of the one of said legs located farthest from said centers of curvature whereby said outer portions of said walls are divergent, the locations of said centers of curvature and the radii of curvature of the curves of the outer portions of said legs differing from each other in location and curvature respectively by an amount corresponding to the difference in the paths of said rollers when moving inwardly and outwardly of the portion of said slot formed between the outer curved portions of said walls of said legs. l

References Cited in the tile of this patent UNITED STATES PATENTS Kolland Nov. 24, 1953 

